Here is an excerpt from the log messages:
Mar 23 12:06:14 arrakis dm: rundm startup succeeded
Mar 23 12:06:27 arrakis gdm: gdm_slave_xioerror_handler: Fatal X error - Restarting :0
Mar 23 12:06:29 arrakis xfs: xfs startup succeeded
Mar 23 12:06:30 arrakis xfs: listening on port -1
Restarting X is not good: it takes time.
xfs was started after dm, so this can be an obstackle for a successful start of dm.
xfs should be started before dm.
I suggested 44 for xfs in my initial dm announce in sisyphus@ ml.
Sorry. (I remembered the announcement was somwewhere, but search.altlinux.ru didn\'t find it.)
Fixed in Xfree86-xfs-4.3.0-alt0.31